Mitsubishi A1S65B-S1 Expansion Base Unit

The Mitsubishi A1S65B-S1 is a 5-slot expansion base unit (extension base plate) for the MELSEC-A series programmable logic controller system. It provides mechanical and electrical interconnection for up to five I/O modules and one power supply module, enabling system expansion beyond the capacity of the main base unit. The module is essential for building large-scale control systems requiring extensive I/O points.

System Expansion Capability

The A1S65B-S1 connects to the main base unit (CPU base) via an extension cable, allowing the system to expand I/O capacity beyond the 5-slot main base. The 5 I/O slots can accommodate any combination of AnS series input modules, output modules, or special function modules, including analog I/O, temperature control, and positioning modules. The dedicated power supply slot allows an A1S63P or similar power supply module to provide clean DC power to the I/O modules, maintaining stable operation even with high-current loads.

Robust Construction for Industrial Environments

The base unit is constructed with high-grade materials to withstand vibration, temperature variations, and electrical noise typical of industrial control cabinets. The module supports both DIN rail mounting and screw mounting, providing installation flexibility. The backplane incorporates robust bus connectors that ensure reliable communication between the expansion base and the main CPU, even in systems with multiple expansion bases. The maximum system I/O capacity of 128 points supports medium to large-scale automation applications.

Application Domains

The A1S65B-S1 is used in production lines requiring extensive I/O coverage, machine tool control with multiple axes and sensors, packaging systems with many input/output points, material handling systems, and process control applications. It is commonly paired with A1S61PN, A1S62PN, or A1S63P power supply modules to complete the expansion station.